The Islamic State’s advance in Iraq has left Middle Eastern leaders jittery.

As the Islamic State, formerly known as the Islamic State in Iraq and Syria (ISIS), continued its meteoric sweep across Iraq, including setting up a presence along the border with Jordan in recent weeks, reports have surfaced that Israel might intervene on Jordanian King Abdullah’s behalf, fearing the stability of his regime.

The Arab uprisings, which first erupted in Tunisia in 2010, and the resulting regional wars and chaos, came as a surprise to everyone, including intelligence agencies.

While no one can be faulted for failing to predict the future, these dramatic developments are having a profound influence on how governments and leaders interpret events – often anticipating the worst no matter how unlikely.

Prime Minister Binyamin Netanyahu said last week that Jordan “knows how to defend itself,” but in the next sentence cast doubt on the veracity of the claim, saying “Precisely for this reason, it deserves international support.”

Jordan’s stability is one of Israel’s vital national security interests, and Jerusalem will do everything to preserve that stability, Foreign Minister Avigdor Liberman said in Berlin on Monday.

“If Jordan asks for assistance in the struggle against the ISIS, we must help,” former National Security Council head Yaakov Amidror told Army Radio last week.

The Islamic State terrorist group will not limit its attacks to within Syria and Iraq, senior Obama administration officials told senators in a classified briefing, The Daily Beast reported a week ago.

“The concern was that Jordan could not repel a full assault from ISIS on its own at this point,” one senator said.

The Obama administration said that it believed that if the Jordanian regime’s existence were in the balance, it would request US and Israeli intervention.

“Israeli diplomats have told their American counterparts that Israel would be prepared to take military action to save the Hashemite Kingdom,” the report said.

However, some experts that are closely following events in Jordan, believe that the threat is being exaggerated.

“Anyone who thinks ISIS – now just IS, the Islamic State – is going to overrun the Jordanian military doesn’t know what is going on,” Kirk Sowell, principal of Uticensis Risk Services, a Middle East-focused political risk firm, told The Jerusalem Post on Tuesday.

“The Jordanians would stand and fight and defeat any frontal assault,” said Sowell, pointing out that “the real security threat in Jordan is a return of Zarqawi-style hotel bombings, and then of course there is the economic burden of the refugees which is a huge problem.”

Sowell dismissed any talk of the IS toppling Abdullah.

“The Jordanians may be playing it up to get more aid, they do that a lot,” he said. “Or it may just be ignorance, people thinking that the Jordanian tribal army is somehow comparable to largely Sunni military units in Iraq fighting under Shia command.”

There is no comparison between the two, said Sowell.

Despite the unlikelihood of Jordan’s government being overrun by IS, Israeli security experts are not taking any chances in their analysis.

Chuck Freilich, a senior fellow at the Belfer Center of Harvard’s Kennedy School of Government and a former deputy national security adviser in Israel, told the Post that Jordan’s stability is the “foremost” national security interest for Israel as it serves as a bulwark against “the entire radical Arab world beyond – in Syria, Iraq and even Iran.”

Jordan is an “island of stability at a time when the entire Arab world is in a state of flux and much of it being redrawn,” he said The former Israeli defense official does not believe the threat is being overblown or that there are any ulterior motives at play.

Taking over Syria and Iraq is one thing, but Jordan falling would “bring the ISIS threat to the very heart of Israel,” Freilich said.

Israel as well as the US should be quietly supporting Jordan with intelligence and some arms, but nothing overt at this point as it “would discredit the king and threaten his position,” he said.

On Netanyahu’s plan to build a fence along the Jordanian border, Freilich said he has long thought that this would be necessary.

“Should Jordan ultimately collapse, it would open up new and potentially dramatic possibilities for dealing with the Palestinian issue, but all our attention should be focused at this point on trying to help ensure Jordan’s ongoing stability and security,” said Freilich.

Jordan’s king seems to be leaving nothing to chance, although Marwan Muasher, a former Jordanian foreign minister, told Newsweek last week that IS and other Islamists are “a concern, but not an existential threat.”

Dr. Dina Lisnyansky, an expert on Islamist movements, a research fellow in the Middle East department at the University of Haifa and co-founder of the Israeli Center for Russian and Eurasian Studies (ICRES), told the Post that Abdullah’s visit in June to Russia’s Chechnya republic to strengthen ties with its leader, Ramzan Kadyrov, raised many eyebrows.

There is speculation that Abdullah is concerned about radical ideologies gaining roots in the Chechen community in Jordan, estimated at around 15,000 people, said Lisnyansky.

A significant number of Chechen mujahideen (jihadis) were spotted over the past two years in Syria and Iraq, she said.

“Most of the Chechen fighters joined the foreigners’ division, or the Muhajireen Brigade that was briefly associated with ISIS,” explained Lisnyansky.

The king is worried about the infiltration of Chechen fighters from IS, possibly entering the country as “refugees.”

Lisnyansky believes that Abdullah’s concern is not exaggerated.

And as the chaos continues in the region, we should expect regional and Western leaders to continue to be overly cautious in their assessments, anticipating scenarios that may or may not play out.